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Ethnopharmacological Relevance: The orchid Prosthechea karwinskii is a species endemic to Mexico, which is used in traditional medicine to lower glucose levels in patients with diabetes, and to treat inflammation-related problems. Recent studies have shown that this orchids can reduce glucose, cholesterol, and triglyceride levels in Wistar rats, which were previously induced to have metabolic syndrome (MS)., Aim of the Study: To evaluate the effect of P. karwinskii leaves extract on the components of metabolic syndrome: obesity, insulin resistance, pro-inflammatory status, and cardiovascular risk in a Wistar rat model, and to identify the bioactive compounds in the extract., Materials and Methods: UPLC-ESI-qTOF-MS/MS was used to identify the compounds present in the extract. MS was induced in Wistar rats through administration of a 40% sucrose diet for 20 weeks. The rats were divided into five groups that received different treatments for 4 weeks: one group without any treatment, one group receiving metformin (200 mg/kg p.o.), and three groups receiving different doses of P. karwinskii leaves extract (100, 200, and 300 mg/kg p.o.). The animals' body weights were recorded weekly, and at the end of the experiment, they were sacrificed after fasting for 18 h to determine the levels of glucose, insulin, insulin resistance index, total cholesterol, triglycerides, and adiponectin in the serum, as well as levels of TNF-α and HS-CRP in the serum and liver homogenates. The abdominal and pericardial fat weights were also recorded., Results: The main bioactive compounds of the extract were quinic acid, neochlorogenic acid, chlorogenic acid, rutin, kaempferol-3-o-β-rutinoside, and embelin, known to exhibit MS-related bioactivity. Oral administration of P. karwinskii leaves extract at a dose of 300 mg/kg decreased weight gain, abdominal and pericardial fat deposits, and insulin resistance. At the end of the treatment, levels of triglycerides, TNF-α, HS-CRP, and adiponectin returned to levels similar to normal., Conclusion: P. karwinskii extract (300 mg/kg) had an anti-obesity effect, decreased insulin resistance, pro-inflammatory status, and cardiovascular risk in rats with induced MS by increasing adiponectin levels and decreasing TNF-α and HS-CRP levels. The compounds identified in the extract could be responsible for these effects, acting alone or in synergy, as several compounds in the extract are known to have MS-related bioactivity. The foliar extract of P. karwinskii has potential as an effective alternative to a cocktail of drugs used to treat problems associated with MS., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Ethnopharmacological Relevance: Prosthechea karwinskii (Mart.) J.M.H. Shaw is a Mexican orchid used in traditional medicine by some indigenous communities to treat issues related to inflammation (cough, wounds, burns, and diabetes). Pharmacological research of this orchid could validate its therapeutic uses and demonstrate its potential for treating other health conditions of high prevalence in Mexico, including those associated with oxidative stress such as diabetes, cancer, atherosclerosis, and hypertension as well as inflammation., Aim of the Study: The leaf extract from P. karwinskii was examined to identify its compounds and elucidate its inhibitory effect on reactive oxygen species as well as its anti-inflammatory activity and gastroprotective effects in an animal model., Materials and Methods: Compounds were identified via ultra-high-performance liquid chromatography coupled with electrospray ionization with quadrupole time of flight-mass spectrometry. Inhibition of reactive oxygen species was determined ex vivo in peripheral blood mononuclear cells with 2',7'-dichlorodihydrofluorescein diacetate. The anti-inflammatory activity was assessed using a carrageenan-induced paw edema model in Wistar rats; nitric oxide and tumor necrosis factor alpha levels were quantified. The gastroprotective effect was evaluated in Wistar rats with indomethacin-induced gastric injury., Results: Nine compounds were identified in the P. karwinskii leaf extract. Most compounds, such as quinic acid, malic acid, neochlorogenic acid, chlorogenic acid, rutin, embelin, pinellic acid, and azelaic acid, were reported to exhibit antioxidant and/or anti-inflammatory activity. The extract was also found to inhibit reactive oxygen species in the ex vivo model. Unlike other anti-inflammatory drugs, the extract exerted a dual effect: anti-inflammatory activity and protection of the gastric mucosa. The results showed that the extract could significantly inhibit the release of nitric oxide without a dose-response relationship., Conclusion: P. karwinskii leaf extract inhibited reactive oxygen species and exerted an anti-inflammatory effect. Moreover, this extract did not induce gastric damage in the animals. The bioactivity of the species was found to support its use in traditional medicine. This orchid could be used to treat inflammatory diseases without causing the side effects associated with nonsteroidal anti-inflammatory drugs. It can also be employed to treat other pathological conditions associated with oxidative stress. The findings herein form the basis for the future discovery of natural products that may serve as safe alternative therapies for inflammatory disorders., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)